bug 3991: spamd can now listen on UNIX domain, TCP, and SSL sockets simultaneously. Command-line semantics extended slightly, although fully backwards compatibly; add the --ssl-port switch to allow TCP and SSL listening at the same time.

more complete IPv6 support.

spamc: add '-z' switch, which compresses mails to be scanned using zlib compression; very useful for long-distance use of spamc over the internet.

bug 5296: spamc '--headers' switch, which scans messages and transmits back just rewritten headers. This is more bandwidth-efficient than the normal mode of scanning, but only works for 'report_safe 0'.

Bump spamc/spamd's protocol version to 1.4, to reflect new HEADERS verb used for '--headers'.

add two features to core rule-parsing code; 1. optional behaviour to recurse through subdirs looking for .cf/.pre's, to support rules compilers working on rulesrc dir. 2. call back into invoking code on lint failure, so rule compiler can detect which rules exactly fail the lint check.